Ranchers in the Owens Valley didn't take too kindly to the aqueduct that drained their underground springs and
diverted water to Los Angeles. By 1924, the predecessor agencies to the city of L.A.'s Department of Water and Power had experienced
several instances of sabotage. The St. Francis Dam in San Francisquito Canyon was
intended to serve as a backup supply in case the flow of Owens Valley water was interrupted. Construction began in August, 1924.

Water began to fill the reservoir above the dam on March 1, 1926. Two months later the dam was finished, at a height
of 185 feet. The reservoir held 12½ billion gallons of water, about a year's supply for otherwise-dry Los Angeles.

At 11:57:30 on the night of March 12, 1928, half of the dam suddenly collapsed. An immense wall of water
rushed down the canyon at 18 miles per hour, totally decimating the concete-and-steel Powerhouse No. 2 hydroelectric generating station
as well as the Frank LeBrun Ranch, the Harry Carey Ranch and Trading Post, and everything else that stood in the way. Floodwaters met
the Santa Clara River at Castaic Junction and headed west toward the Pacific Ocean. The communities
of Piru, Fillmore, Santa Paula, Saticoy and much of Ventura were leveled before the water, mud and debris completed their
54-mile journey to the ocean at 5:25 a.m. on March 13th.

At dawn's early light, an estimated 411 people lay dead. Some bodies were buried under
several feet of earth and were still being discovered in the 1950s. In fact, remains believed to be those of a dam victim
were found in 1994. The disaster that ended the career of the famous engineer and DWP chief William Mulholland
was the second-worst disaster in California history in terms of lives lost, surpassed only by the great San Francisco earthquake and fire of 1906.